Virtually every off-the-shelf ecommerce platform comes with built-in functionality for capturing email addresses during the checkout process, as well as other opt-in methods you may use. Given the the competition ecommerce stores face, you should be doing everything you can to capture the maximum number of leads.

You might feel that opt-ins and pop-up lightboxes are intrusive. You might even think that people hate them, but these methods get results and drive a lot more subscribers than the default "Also subscribe me" checkbox your customers only see during the checkout process.

Marketer and blogger Darren Rowse was concerned about annoying visitors when he added a lightbox opt-in to his site to try to increase his rate from 40 subscribers per day, but he couldn't have been happier with the results of his test.

"Considering pageviews per visitor didn't go down and I'm adding 350 or so new potential weekly readers to my blog each day, I'd say reader engagement has actually significantly been increasing," Rowse said.

For ecommerce businesses, though, you're not just looking for readers. The content you send via email is far more important than your sign-up tools and methods, especially if you want to turn subscribers into customers and increase revenue.

Here are seven types of autoresponder emails you should schedule to stay top-of-mind with your growing subscriber base.

1. Cart Abandonment Autoresponders

On average, 68% of people abandon online shopping carts, with shipping costs flagged as the main reason. Although there are a number of other reasons for cart abandonment, you can regain a lot of that lost revenue through cart abandonment autoresponders.

Create a sequence that triggers when a visitor abandons a cart to remind them of the items they were considering. This is usually a series of emails that provide a discount coupon or social proof about the items left in the cart. Basically, these emails include information to help the customer overcome their top objections.

2. General Lead Nurture Autoresponders

Stores with a lower average order value or less expensive items don't always require nurturing, but it doesn't hurt. A lead nurture autoresponder delivers on the incentives you offered to get your leads to opt-in.

Over the course of several emails, you can use content marketing to educate and build the relationship, while leveraging social proof and incentives to steer the buying decision around non-promotional content.

"Nobody who bought a drill wanted a drill,"writes Perry Marshall, marketer and author of 80/20 Sales and Marketing. "They wanted a hole. What this means for you is that instead of providing information about drills, you should deliver more information about making holes. You'll get a lot more sales leads--with fewer literature collectors--and build more rapport with prospective customers that way."

3. Customer Campaign Autoresponders

Marketing shouldn't end once a purchase is made. Create an autoresponder series that keeps the customer engaged post-purchase. This should include a welcome and thank you email.

Depending on the product, you could send additional emails that include instructions about the product, along with recommendations for similar items that go well with what they purchased.

Include emails that ask if they received their items and if they're happy with their purchase. Include links and a call-to-action to allow the customer to review the product at your store or on social media. Don't miss an opportunity to leverage social proof and testimonials.

Watch your metrics for the average length of time it takes a customer to make a return purchase. Schedule an email as part of this series that includes a cross-sell. Also, incentives can help boost the number of returning visitors.

4. Confirmation Autoresponders

Confirmation emails for orders and and shipping will typically have higher open rates than other emails you send. Take advantage of the eyeballs and optimize those emails. Include recommendations for your top products, or make recommendations for products that align with what they purchased. This is also a good opportunity to add a "thank you" incentive for their next order, as well as trigger a viral loop referral.

5. Abandonment-During-Browsing Autoresponders

I recently had the opportunity to interview Rob Walling, founder of Drip, an email marketing automation platform. One of the great features of Drip is the ability to trigger email campaigns when someone visits a specific page at your store.

Instead of limiting your follow-up to simply address cart abandonment, you can send your customers an autoresponder when they visit top products. It's a great way to survey people about why they left, or use elements like social proof to overcome objections that bring them back to make a purchase.

6. Custom Funnel Autoresponders

If your email platform has the capacity to set up multiple funnels based on user behavior and intent, I highly recommend doing this. Tag visitors based on what they viewed, as well as their onsite behavior.

Ask visitors why they didn't make a purchase, and work to identify their objections. Use that information to improve future emails and provide conversion points for objections. You can also provide social proof specific to the custom funnel autoresponders, as well as stories and case studies that are most relevant to that specific audience.

If all else fails, include a last-ditch discount to convert them.

7. Lost Customer Autoresponders

For most Ecommerce stores that rely on return visitors, you're in danger of losing people completely if they haven't made a purchase in the last 90 days. The same goes for those who haven't opened, clicked on or responded to an email in 60-plus days.

Create a "missing you" autoresponder that lets them know you're thinking about them because you haven't seen them in a while. Make this an incentivized email with a subject line that makes the incentive clear. Use deep discounts to re-activate subscribers and drive engagement. Add finality with an ultimatum by letting them know that if they don't take action they'll be unsubscribed.

What types of autoresponders do you use to improve revenue and boost sales in your online store? Share yours with me in the comments below: